Self-Consistent Far-Field Blooming Analysis for High-Power Fabry-Perot Laser Diodes

摘要

High-power broad-area laser diodes often suffer from a widening of the lateral far-field with rising current injection. This effect is also referred to as thermal blooming, since self-heating is considered the main cause. The non-uniform temperature profile inside the waveguide leads to a lateral refractive index profile that enhances the index guiding of laser modes (thermal lens). This paper presents a self-consistent electro-thermal-optical simulation and analysis of the thermal blooming effect, including the non-uniform heat power distribution inside the laser as well as the non-uniform carrier and gain distributions inside the quantum wells. The calculated results are in good agreement with measurements. The simulations demonstrate that thermal blooming is not only caused by the rising order of lateral modes but also by the far field widening of each individual mode with increasing current.